1. Field of the Invention
The present invention relates to the field of the transmission mechanism, and more particularly to a mechanism for adjusting the rotation direction and speed of an inner ring and an outer ring of a rotary bearing.
2. Description of Related Art
Usually, a rotary mechanism comprises: 1. Contact type rotary bearing includes a shaft and a rotary bearing, and the rotary bearing include ball bearings, roller bearings or needle bearings; 2. Non-contact type rotary bearing includes a shaft and the hydraulic bearings, the shaft and the air bearing and so on. Under normal operating conditions, the contact type bearing often generates wear problem, and the non-contact type bearings require regularly replacing the fluid, the gaskets and the seals because of high viscous liquid or the higher pressure gas.
In order to maintain the rigidity and accuracy requirements of the rotary system, the contact portion between the shaft and the inner surface of the rotary bearing require adhesion to make no relative movement. The outer surface of the rotary bearing is also required to adhere with the support frame, so that the two have no relative movement.
In some applications, the support frame is fixed without moving, and only the shaft is rotating. In this case, the inner ring of the rotary bearing rotates with the shaft, while the outer ring does not move. On the contrary, in some applications, the shaft is fixed without moving and the support frame is rotating. In this case, the outer ring of the rotary bearing rotates with support frame, while the shaft and the inner ring do not move
Although in the conventional art, the rotary mechanism can meet the requirements of the system rigidity and accuracy. However, in the applications of the contact rotary bearing, it cannot avoid the inner wear problem of the rolling elements. When the inner wear problem reaches a certain level, it must be promptly replaced bearing, which is time consuming particularly for the replacement of heavy equipment. In the application of the non-contact type rotary bearing, it is necessary to use the high viscous liquid or high pressure gas for the equipment of the high load, and therefore it required periodic replacement of the fluid, the leak-proof gaskets, and the seals.